Evolution And Probabilities: A Response to Jason Rosenhouse

I recently published an article on Uncommon Descent on the value of probabilistic arguments in the evolution debate. Mathematician and ScienceBlogs contributor Jason Rosenhouse has since responded with a rebuttal on his blog. Here, I offer a brief response.

Rosenhouse writes,

Jonathan M. is completely confused about what the issue is. Pigliucci certainly never claimed that biologists are not interested in evaluating probabilistic feasibility (whatever that even means). He said simply that evolutionary biologists do not assign probabilities to specific events in the way that ID folks would like.

For example, Jonathan M. points to a calculation in which biologist Sean Carroll estimated the probability of obtaining the same mutation four times independently in different orders of birds. In such a narrowly defined situation the problem has more to do with combinatorics than probability, and we can be confident that all of the relevant variables can be approximated with reasonable accuracy.

He also points to a paper by Durrett and Schmidt, in which they evaluated the probability of obtaining two particular mutations in at least one individual of a population. Once again, in such a narrowly defined situation it is possible to get a grip on all of the relevant variables. But notice that neither they, nor Carroll, were trying to calculate the probability of evolving a flagellum or anything remotely like that.

While it is true that the individuals in question do not attempt to calculate the probability of something of the complexity of a bacterial flagellum, to handwavingly assert that such calculations have no bearing whatsoever on questions such as this seems to me to be somewhat naive.

For example, let’s grant for purposes of our argument here that the conclusions reached in Douglas Axe’s bacterial population model are correct: That is, if a duplicated gene is neutral, then the maximum number of mutations that a novel innovation in a bacterial population can require is up to six, whereas if the duplicated gene has a slightly negative fitness cost, the maximum number drops to two or fewer. If one can demonstrate that the evolutionary steps to a functioning flagellum would likely require more co-ordinated mutations than this at the individual stages, then — even though the exact probability of the flagellum may not be directly calculable — it seems to be a plausible inference that the flagellum lies beyond the reach of the Darwinian mechanism.

But here’s the thing. According to Douglas Axe’s more recent research, done in collaboration with Ann Gauger, even a seemingly trivial switch from Kbl to BioF function requires at least seven co-ordinated mutations, putting the transition well beyond the reach of a Darwinian process within the time allowed by the age of the earth. Their paper studies the PLP-dependent transferases superfamily. They identified a pair within the superfamily with close structural similarity but no overlapping function. The enzymes chosen were Kbl (which is involved in threonine metabolism) and BioF (which is part of the biotin synthesis pathway). And they used a three-stage process (which you can read about here) to identify which sequences were most likely to confer a change in function.

And thus they estimated that seven or more mutations would be required to convert Kbl to BioF function.

Axe and Gauger’s paper is not an isolated result. For example, one fairly recent review in Nature reported that changing an enzyme’s chemistry may require multiple neutral or deleterious mutations.

When these results are taken into account in the context of the predictions of population genetics with regards the waiting time for multiple co-ordinated non-adaptive mutations which are required to facilitate a given transition, the situation for neo-Darwinism appears to be bleak.

In the case of the Durrett and Schmidt (2008) paper, evolutionary biologist Richard von Sternberg has applied the equations employed in that paper to whale evolution. The evolution of Dorudon and Basilosaurus (38 mya) may be compressed into a period of less than 15 million years. Such a transition is a fete of genetic rewiring and it is astonishing that it is presumed to have occurred by Darwinian processes in such a short span of time. This problem is accentuated when one considers that the majority of anatomical novelties unique to aquatic cetaceans (Pelagiceti) appeared during just a few million years – probably within 1-3 million years. The equations of population genetics predict that – assuming an effective population size of 100,000 individuals per generation, and a generation turnover time of 5 years – according to Richard Sternberg’s calculations and based on equations of population genetics applied in the Durrett and Schmidt paper, that one may reasonably expect two specific co-ordinated mutations to achieve fixation in the timeframe of around 43.3 million years. When one considers the magnitude of the engineering fete, such a scenario is found to be devoid of credibility. Whales require an intra-abdominal counter current heat exchange system (the testis are inside the body right next to the muscles that generate heat during swimming), they need to possess a ball vertebra because the tail has to move up and down instead of side-to-side, they require a re-organisation of kidney tissue to facilitate the intake of salt water, they require a re-orientation of the fetus for giving birth under water, they require a modification of the mammary glands for the nursing of young under water, the forelimbs have to be transformed into flippers, the hindlimbs need to be substantially reduced, they require a special lung surfactant (the lung has to re-expand very rapidly upon coming up to the surface), etc etc.

Moreover, Michael Behe has shown (see chapter seven of The Edge of Evolution) that the evolution of protein-protein binding sites by Darwinian means is immensely improbable. And Douglas Axe, Robert Sauer, Sean Taylor and others have shown that the preponderance of evolutionarily relevant (i.e. functional) protein folds is astronomically rare within sequence space. These types of problems are only accentuated a thousand fold when one considers systems which, by their very nature, require multiple inter-dependent protein interactions in order to perform their functions.

This paper by Wilf and Ewens, also mentioned in the post, puts some mathematical meat on the bones of Dawkins’ suggestion. They are working with probabilities only indirectly, and certainly were not trying to assign precise numerical values to specific evolutionary events.

The abstract of this paper reported,

Objections to Darwinian evolution are often based on the time required to carry out the necessary mutations. Seemingly, exponential numbers of mutations are needed. We show that such estimates ignore the effects of natural selection, and that the numbers of necessary mutations are thereby reduced to about K log L, rather than KL, where L is the length of the genomic “word,” and K is the number of possible “letters” that can occupy any position in the word. The required theory makes contact with the theory of radix-exchange sorting in theoretical computer science, and the asymptotic analysis of certain sums that occur there.

This sounds awfully like an attempt to demonstrate the probabilistic plausibility of Darwinism to me. We ID proponents employ probabilistic logic as well, in order to ascertain the likelihood of evolutionarily relevant innovations emerging by Darwinian means. Only we reach the opposite conclusions from those reached by Wilf and Ewens. Darwinists are happy for probabilistic reasoning to be employed only when it suits their purposes in vindicating Darwinism. When ID proponents want to use probabilistic arguments to falsify Darwinism, they won’t be having any of it.

If you search the current issues of professional science journals, I doubt you’ll find any papers titled “The Moon Orbits the Earth” or “Copper Conducts Electricity.” Assertions like these would work as section headings in an elementary science textbook, but no scientist would consider them newsworthy, for the simple reason that they aren’t.

Things are different in evolutionary biology, though. Here is a field that somehow never outgrew the need to reiterate its most basic tenets, as though its practitioners never had enough confidence in them to let them stand on their own two feet.

Their model does not mimic natural selection at all. In one generation, according to the model, some number of potentially adaptive mutations may occur, each most likely in a different individual. W&E postulate that these mutations remain in the population and are not changed. Contrary to their intention, this event is not yet evolution, because the mutations have occurred only in single individuals and have not become characteristic of the population. Moreover, W&E have ignored the important fact that a single mutation, even if it has a large selection coefficient, has a high probability of disappearing through random effects [Fisher 1958]. They allow further mutations only in those loci that have not mutated into the “superior” form. It is not clear if they intended that mutations be forbidden in those mutated loci only in those individuals that have the mutation or in other individuals as well. They have ignored the fact that evolution does not occur until an adaptive mutation has taken over the population and thereby becomes a characteristic of the population. Their letter-guessing game is more a parody of the evolutionary process than a model of it. They have not achieved their second goal either.

If Darwinism can’t even handle the trivial, then what chance does it have when it comes to the bigger problems such as building flagella? And if we can’t even evaluate the probabilistic feasibility of the Darwinian mechanism, how can we ever learn whether it is up to the task at hand? Whether they realize it or not, Pigliucci and his ilk have, in effect, rendered Darwinism unfalsifiable.

88 Responses to Evolution And Probabilities: A Response to Jason Rosenhouse

The basic point here is very simple. A proper probability calculation begins with the definition of a probability space, which means roughly that you must have a grasp on all of the things that might happen and also on the probabilities with which those events occur. There are many contexts in evolutionary biology where that can be done. In population genetics, for example, we typically narrow our focus to small numbers of loci over short periods of time, which permits us to get a grip on all of the relevant variables. This is far different from trying to work out precise probabilities for specific structures that evolved over vast stretches of time. In such situations we have no hope of getting a grip on everything.

I’m judging by the context of your citation that you mean the one he did with Ann Gauger. The purpose of that calculation was to estimate how many mutations were required to convert Kbl to BioF function. This fits into the context of his work on bacterial population genetics, which demonstrates the impotence of neo-Darwinism to traverse distances of more than a small handful of non-adaptive mutations. I recommend reading the paper for the specific calculations and means by which he came to those conclusions.

Every argument that ends up with a Darwinist claiming that there isn’t a rigorous probabilistic model that can falsify the capacity of RM* and NS* to acquire the target in question is a de facto admission that no model exists that can demonstrate RM* and NS* up to that same task.

Either a metric exists that can show RM* & NS* up to the macroevolutionary task, or not; if not, it cannot be anything other than a hasty generalization.

If we don’t know what the proper search space is for those targets in question, and we dont know what the limitations to the ability of RM* and NS* are, then it cannot be said that RM* and NS* can search the space and acquire the target, and it certainly cannot be claimed to be a scientific fact that RM* and NS* actually acquired those targets.

But his estimate of 10^30 generations to establish the conversion is based on a probability estimate, for which, as Jason Rosenhouse says, you need to define your probability space.

And, as Jason Rosenhouse says, correctly, IMO, this is simply not possible for a specific structure over long stretches of time, not least because over that time, the organism will have inhabited many different environments.

I keep saying it because it is true. There isn’t any evidence that genetic accidents can accumulate in such a way as to give rise to new, useful multi-part systems, never-mind change a fish into an amphibian or a shell-fish into an insect.

And to me the use of probabilities is moot until someone can demonstrate a feasibility.

I keep saying it because it is true. There isn’t any evidence that genetic accidents can accumulate in such a way as to give rise to new, useful multi-part systems, never-mind change a fish into an amphibian or a shell-fish into an insect.

Well, clearly there is no evidence that has convinced you, but it simply isn’t true that there is no evidence.

Well Elizabeth I was a true believer until I started looking at the “evidence”. That said I may have over-looked something but if I did it must be a well-kept secret.

So what had convinced you that genetic accidents can accumulate in such a way as to give rise to new, useful multi-part systems and change a fish into an amphibian (yes over eons of years and generations) or brine shrimp-like organisms (technically a shellfish) into insects?

Or as Dr Behe asked many years ago:

Let’s turn the tables and ask, how could one falsify the claim that, say, the bacterial flagellum was produced by Darwinian processes?

Well, I guess two things, Joseph: one is the demonstration that “genetic accidents”, when coupled with an environment in which some variants do better than others, results in adaptation, and the other is the observation that biological organisms, both extant and in the fossile record, can be placed on a branching tree, whereby along any given lineage we see gradual change, but resulting in huge variety at the “twigs” of the tree.

So we have an observed pattern, namely a branching tree, and a mechanism, namely replication with heritable variance in the ability to survive the current environment, that could account for it, and indeed, is actually observed occurring.

As for Behe’s question: it would be difficult to falsify. But the theory does not depend for its support on their being a clear Darwinian account for every biological feature. What it depends on is the fit of the model to the data.

What would throw Darwinian theory into doubt would be a serious breakdown of nested phylogenies, in particular, the appearance of “solutions” from one lineage apparently transplanted into another.

This would suggest intelligent interference, and, indeed, our distant descendents may well infer our own genetic engineers from precisely this kind of evidence.

I don’t myself think that “falsification” is a good test of whether a theory is scientific or not. Science doesn’t actually proceed by falsification – it proceeds by fitting models to data.

If an alternative model fit the data better, that would be a challenge to Darwinian theory, and indeed, many such challenges are thrown up regularly, which is why the theory is subject to constant adjustment, even though the basic principle so far remains.

Well, I guess two things, Joseph: one is the demonstration that “genetic accidents”, when coupled with an environment in which some variants do better than others, results in adaptation,

1- Question begging pertaing to “genetic accidents”

2- YECs even accept that

and the other is the observation that biological organisms, both extant and in the fossile record, can be placed on a branching tree, whereby along any given lineage we see gradual change, but resulting in huge variety at the “twigs” of the tree.

Well the allged “tree” is an illusion because as darwin even said if all the forms that ever lived were still around we wouldn’t have that pattern.

Also the theory of evolution is absolutely silent on divergence for by convergence- that is crossings of once diverged lines. That means the mechanism “namely replication with heritable variance in the ability to survive the current environment” does not produce the pattern described.

So the bottom line is you don’t have any evidence that demonstrates genetic accidents can accumulate in such a way as to give rise to new, useful multi-part systems and you don’t have any evidence that a population of fish can “evolve” into something other than fish.

What we actually observe occurring cannot be extrapolated, in any way, to meet the grand claims of evolutionism.

Well the allged “tree” is an illusion because as darwin even said if all the forms that ever lived were still around we wouldn’t have that pattern.

I’m not sure what you are saying here.

Also the theory of evolution is absolutely silent on divergence for by convergence- that is crossings of once diverged lines. That means the mechanism “namely replication with heritable variance in the ability to survive the current environment” does not produce the pattern described.

Nor here

Are you saying convergent evolution is a problem for Darwinian evolution? If so, not unless the convergent phenotypic “solutions” have extremely similar genotypic underpinnings.

Elizabeth Liddle:“And, as Jason Rosenhouse says, correctly, IMO, this is simply not possible for a specific structure over long stretches of time, not least because over that time, the organism will have inhabited many different environments.”

Well, actually this argument is pretty self-defeating. Consider that one of the strongest arguments for common descent is the insertion sites of endogenous retroviruses: they display a nested pattern. And the odds of this occurring by coincidence is next to nil. But one could counter that the nested pattern displayed by ERVs actually is the result of chance, ’cause we can’t calculate the probability of that pattern arising by chance ’cause over the time that the ERVs inserted themselves into various organisms, those organisms went through different environments and conditions. The same argument could be made with regards to molecular phylogenies.

What would throw Darwinian theory into doubt would be a serious breakdown of nested phylogenies, in particular, the appearance of “solutions” from one lineage apparently transplanted into another.

Like wings on birds, bats, and insects? Like reptiles and octopi that change colors? Like echolocation in bats and dolphins? Like mammals shaped like fish? Like mammalian lungs and countless other features that apparently must have arisen more than once?

Every known “solution” that appears in differing lineages has already been explained away as convergent evolution and the like. (There were niches in both fitness landscapes shaped like animals that use echolocation.) So really, wouldn’t any other astounding similarity just get explained away? ‘Wow, isn’t this amazing that this evolved twice?’ If anything, it would become the next amazing example of the power of evolution.

Or are we setting ridiculously high standards for falsification, like pre-Cambrian rabbits? If a bird sprouted eight legs, started spinning webs and catching flies, then it would ‘throw Darwinian theory into doubt?’

Joseph: You say you were once a “true believer”; are you the same Joseph who came here to UD a couple years back and defended Darwinism? I must say I’m a little confused when I see your posts and then see that you’ve (apparently) adopted an ID perspective.

That is, if a duplicated gene is neutral, then the maximum number of mutations that a novel innovation in a bacterial population can require is up to six, whereas if the duplicated gene has a slightly negative fitness cost, the maximum number drops to two or fewer. If one can demonstrate that the evolutionary steps to a functioning flagellum would likely require more co-ordinated mutations than this at the individual stages, then — even though the exact probability of the flagellum may not be directly calculable — it seems to be a plausible inference that the flagellum lies beyond the reach of the Darwinian mechanism. (emphasis added)

I hope it’s clear that this conclusion assumes that evolution by natural selection is not a “Darwinian mechanism”.

But here’s the thing. According to Douglas Axe’s more recent research, done in collaboration with Ann Gauger, even a seemingly trivial switch from Kbl to BioF function requires at least seven co-ordinated mutations, putting the transition well beyond the reach of a Darwinian process within the time allowed by the age of the earth. Their paper studies the PLP-dependent transferases superfamily. They identified a pair within the superfamily with close structural similarity but no overlapping function.

Gauger & Axe compared 2 proteins that showed structural similarity, they don’t showed any data for the similarity of their DNA sequences, i.e. we’re not told how far apart they are evolutionarily. But if one evolved from another, it’s the evolutionary distance that needs to be traversed. It’s perfectly possible that there is a pathway from a common ancestor to both proteins where every intermediate had a fitness advantage. Hopefully Gauger & Axe are looking at this now.

Essentially, the probability density functions of all the variables in your claim. So that’s fairly easy to do for a given sequence of nucleotides, but rapidly becomes virtually impossible once you start to tackle things like the selection coefficient of each mutation at any given time, or the number of equivalent functions, and what their probability is of evolving, etc.

It’s partly a problem intrinsic to computing post hoc probabilities – you can’t really do it unless you have a good handle on what else might have happened.

Well, bat wings on birds or bird wings on insects would certainly be a problem for evolution. But the base example of wings is just another example of convergent evolution (i.e physical necessity dictates it).

The same is true for mammals shaped like fish (and ichthyosaurs, too) – it’s the most efficient dynamic shape for speed in fluid environments, and hence very likely to be selected for. Hence the convergence.

So the general evolution of physically advantageous features, such as sleek body shapes in fluid environs, is not surprising.

It’s the detail that would falsify Darwiniam theory – as evolution only works on what is available, then it would be a problem for the theory if bat wings sprouted bird feathers, for example, but wings are necessary for flight hence their use, in different forms, across the animal kingdom.

For the same reason, birds spinning webs and sprouting eight legs would be a falsification of Darwinian theory.

Lungs are interesting, because their use in marine mammals potentially falsify ID, I think. If there is a designer, why didn’t it ever design a mammal – not one species – with gills instead of lungs?

“Not really. At least I’m not seeing your point. You could fairly easily compute the probability of a specific sequence occurring by chance in a nested pattern.”

Well, no, because you don’t know all the variables that were behind the fixation of a given sequence in a population. Human cytochrome c is more similar to mouse cytochrome c than to carp cytochrome c, but one could argue that this is the result of chance. After all, by Jason Rosenhouse’s argument, you don’t know what environments each species has been in, and so it’s very difficult to compute the odds of that pattern occurring by chance.

So, JonathanM — what’s the probability of the Grand Canyon? Go on, calculate it, if you think evolutionists should do such calculations for complex biological systems, it ought to be easy for you to do it for the Grand Canyon.

This sort of challenge simply reveals the paucity of your actual evidence.

If you actually had any serious observational evidence for body plan origins by chance variation and differential survival of unicellular organisms several hundred mn ya, you would be shouting from the housetops.

We are now able to show that random evolution will become cumulative and will reach fitness BB(N) in time that grows roughly as N2, so that random evolution behaves much more like intelligent design than it does like exhaustive search. We also have a version of our model in which we can show that hierarchical structure will evolve, a conspicuous feature of biological organisms that previously was beyond our reach.

If, however, we suppose any descendant of A or of I to have become so much modified as to have lost all traces of its parentage in this case, its place in the natural system will be lost, as seems to have occurred with some few existing organisms.-Charles Darwin chapter 14

Extinction has only defined the groups: it has by no means made them; for if every form which has ever lived on this earth were suddenly to reappear, though it would be quite impossible to give definitions by which each group could be distinguished, still a natural classification, or at least a natural arrangement, would be possible.- Charles Darwin chapter 14

“Well, the point about the different environments is that that will effect the selection coefficients.”

Exactly. So given the fact that each species has inhabited different environments, we can’t really calculate the odds of a given nested pattern being displayed by a nucleotide sequence, unless you assume that all those sequences are neutral with respect to fitness. But that’s an assumption, and given that all species have inhabited different environments, and therefore you don’t know if those sequences were neutral or not at some point, that assumption is not justified.

Does the Grand Canyon represent some specified pattern, known beforehand?

Can it be recognized and be put to use by anything?

If the answer to either of these questions is, no, then we’re not dealing with anything quite like biological function.

From what I understand, running water erodes. So, I would suspect rapidly running water carved out the GC. I’m satisfied with that explanation. Are you satisfied that highly specified molecular configurations arose from pure chance? I’m not.

You’re wrong. Just as the probability of the Grand Canyon is “basically 1 given certain parameters”, similarly the probability of alligators is 1 “given certain parameters” – as is the probability of human beings “given certain parameters”.

The probability of that particular canyon, with those particular features, is vanishingly small. Yet it occurred.

Same with adaptation. The probability of a population adapting to its environment is extremely high. The probability of any given adaptation, with any given set of features, is vanishingly small. Yet it occurs.

What people are claiming (me for instance, and Nick) is that adaptation is just about as predictable as the erosion of running water – you can’t predict what form the adaptation will take, but you can predict adaptation.

I should also say, I think it’s probably a great mistake to assume that most evolutionary novelties were advantageous at their first appearance. My hunch is that the vast majority of novelties – variants – are neutral, or near-neutral at their first appearance, and of those, a substantial proportion become quite prevalent variants in the population simply through drift.

Then, when an environmental change occurs, or when two neutral mutations, already present in the gene pool, coincide in one individual to form an advantageous trait, both become more prevalent. In other words, “microevolution” is no different to “macro-evolution” – both are the result of biased selection of alleles already having substantial prevalence in the gene pool.

By that argument absolutely anything is possible. A monkey can type Shakespeare because the exact configuration of blades of grass on the earth is highly improbable, and yet there it is.

I can throw a lump of dirt at a wall, and the exact configuration of sand and rocks will be highly improbable. So is it reasonable to expect that it might turn into a life form? After all, both are improbable.

Tonight I’m going to teach my five year old how to see through that reasoning.

Ever heard of the statistical weight of a macrostate? (Aka, thermodynamic probability.)

When states come in identifiable clumps, the relative sizes of the clumps can be important.

The key idea of FSCI is that the functional state we may observe comes from a relatively narrow and unrepresentative zone of possibilities, as opposed to the overwhelming number of unspecified gibberish states. When that happens, an unintelligent sampling of the space is overwhelmingly likely to land in typical — gibberish — states. BTW, this is very close to the reasoning behind the 2nd law of thermodynamics, as has been repeatedly pointed out.

Under the relevant likely forces at work, a canyon of large size was an overwhelmingly probable outcome, and the particular outcome comes from an overwhelming cluster of possibilities.

If on the other hand we had seen smooth-sided canal like features, similar to the Panama canal or the one at the Isthmus of Corinth, that would have been a giveaway that this was an artifact.

It seems that to discuss speciation, one would have to have a solid definition of “species”. Is the concept more clear than the Wikipedia article (on “species”) makes it sound when it says, “Over two dozen distinct definitions of ‘species’ are in use amongst biologists.”?

The first quote says life is a tree, but sometimes creatures evolve is such a way it’s difficult for humans to place them in that tree (cf Placazoa)

The second one seems to be saying specifically that there is a tree – that there is a natural pattern which could be used to group species even if we had all the transitional forms which would do away with traditional taxonomic distinctions.

But you don’t have to go to The Origin to know what evolution predicts – speciation is a very basic part of evolutionary biology. Speciation makes lineages which go off to explore (and change) the fitness landscape on their own which is why, say, bats and birds have such different wings to do the same job.

Agreed, actually; but it ain’t over with “test,” it’s then onto more and more questions with the results of tests before you can actually arrive at conclusions. And if you start with the wrong hunches (assumptions) you may end up with incorrect interpretations of results. That’s why you must try to rule out other possibilities; which is not what Darwinists have done. What they’ve done is to implement their little tests (GAs for example) and then run with the results saying: “see, this proves evolution,” without actually asking any further questions:

Are my hunches (assumptions correct)? Is random mutation and natural selection the only possibility, or could something else be going on? e&….

In other words, it’s very easy to “prove” what you’ve already assumed by your hunch. Did it ever occur to you that the most reasonable assumption would be based on the issue of probabilities?

Let’s take clairvoyance for example: James Randi is offering $1,000,000 to anyone who can demonstrate clairvoyance. Why is he being so bold? It all has to do with probabilities. It is highly improbable that clairvoyance is genuine.

Now let’s assume that you applied your hunch-followed by theory/hypothesis/test method to clairvoyance. Well, ok, you assume at the beginning that there ARE instances of genuine clairvoyance. So you theorize. Then you hypothesize that a 33% success rate in a controlled setting would be evidence of clairvoyance, since it’s above the 25% threshold of chance with such “predictions.” You predict (since you already believe that clairvoyance is genuine) that you will get the desired results. And lo and behold, in one instance of amazing accuracy, you arrive at 32%; a little less than you predicted, but you’re ok with it. You publish your results in a peer reviewed parapsychology journal and voila. It becomes fact.

Actually, according to Wiki, such a test was done:

“One controlled procedure has invited ‘senders’ to telepathically transmit one of four visual images to ‘receivers’ deprived of sensation in a nearby chamber (Bem & Honorton, 1994). The result? A reported 32 percent accurate response rate, surpassing the chance rate of 25 percent.”

Question: If Darwinian evolution depends on similar but much lower probabilities than clairvoyance, why don’t your “hunch meters” turn on? They ought to have some sort of automatic switch that goes on when you’re faced with near impossible odds, don’t you think?

And if for scientifically minded people, the issue of clairvoyance rests in the probabilities, why doesn’t the issue of RM + NS also rest in the probabilities; which are next to zilch?

The “clairvoyants” actually have one up on you. At least they’ve been bold enough to attempt to demonstrate it. Where’s the claimed instance of RM + NS producing novel features under controlled tests? Well it ain’t happening because it can’t be. It’s an issue of long periods of time for which anybody’s guess is accepted provided they can make it stick with “scientificiness” (that’s scientific sounding truthiness.

I suppose you’re going to say “well, Darwinian RM + NS has been involved in more than just one particular study; so the analogy is bogus.” Well, no. Throwing 3,000,000 arrows towards a target and missing gets you the same results as throwing just one arrow towards a target and missing. You’d think by now those odds would mean something to you.

For some curious reason I can’t put a comment under your comment #2.1.1.1.2. Anyway, what do you think is better: to come up with an estimate which maybe crude or to say we can’t say anything?

You willl agree with me if I say that In general when doing research you come up with something that fits your data and revise it, if necessary, as soon as more data becomes available. If you have no data, you may resort to “common sense” and come up with some “zero-knowledge default” model that you can work with, again until such times as (more) data is available.

In fact, I read an article by Douglas Axe where he proposed a conservative estimate and he explained why it was conservative. He deliberates at length in response to criticisms at his Biological Institute’s website. IMHO, this is far better that to say we can’t establish an estimate. Because if we can’t, why bother?

I too have become disillusioned by Darwin’s thoughts. His mistake was to extrapolate too widely what he observed to be a variation within a species. It just does not work that way! But as of the 19th century that was really a good try.

In defence of Darwin personally, I can say that he was really careful in his scientific investigations, wrote wonderfully and phrased his hypotheses very accurately (which unfortunately cannot be said about many of his followers). His “On Origin of Species” is an interesting reading. But, alas, that was a big mistake to generalise his findings too widely.

Yes, I know. But typically I hear the amazing adaptive powers of RM+NS described as more than a hunch. If you’re still speculating about the mechanics then apparently you haven’t come across anything that’s convinced you much.

It seems that to discuss speciation, one would have to have a solid definition of “species”. Is the concept more clear than the Wikipedia article (on “species”) makes it sound when it says, “Over two dozen distinct definitions of ‘species’ are in use amongst biologists.”?

Interestingly, no.

The concept of speciation is completely unambiguous, at least for sexually reproducing populations. That doesn’t mean that it isn’t a process that takes place over times, and remains somewhat reversible for quite a while, making the point at which you declare that it has finished i.e. where you declare you have two separate species, somewhat arbitrary.

But that doesn’t make the concept ambiguous at all, any more than the concept of development is ambiguous, even though it is hard to say precisely when a child becomes an adult, as reflected in the term “adolescence”.

If, however, we suppose any descendant of A or of I to have become so much modified as to have lost all traces of its parentage in this case, its place in the natural system will be lost, as seems to have occurred with some few existing organisms.-Charles Darwin chapter 14

That means the tree will be artificial.

Extinction has only defined the groups: it has by no means made them; for if every form which has ever lived on this earth were suddenly to reappear, though it would be quite impossible to give definitions by which each group could be distinguished, still a natural classification, or at least a natural arrangement, would be possible.- Charles Darwin chapter 14

The tree requires those (impossible) definitions to determine the population’s place on it. No definitions, no tree.

My argument works for both ERV phylogenies and other molecular phylogenies. But I’ll stick with ERV phylogenies:
Consider that both chimpanzees and humans share a number of chromosomes located in the same position in their genomes — implying common ancestry. The odds of this occurring by chance is next to nil, BUT we could argue: you don’t know what environments chimps and humans have been in, in the past, so you can’t say that it must be the result of common ancestry. It could actually be that those ERVs were inserted independently in each lineage and then kept in each lineage because they offered a selective advantage. You can’t argue against that, ’cause after all we don’t know the environments that both species were in, right?

It’s not remotely credible that any new evidence of any kind could throw Darwinian theory into doubt. The use of probability or empirical evidence to determine what may or may not happened has already been tossed to the wind.
Suppose you find a frog with opposing thumbs that flies like bat and spins webs.

What are you going to say – its evolution would be improbable? Is it more improbable than the exact shape of the Grand Canyon? You have forfeited the use of probability to determine which events are more or less likely to have occurred. When you speak of probability, it is abstract, meaningless.

Or will you say that Darwinian evolution is not the best explanation? That’s hasn’t stopped anyone yet. When Dawkins wants to wow us with real-life observations of evolution in progress he uses the changing sizes of lizard heads. And from that you extrapolate spiderwebs and echolocation, etc. etc., etc. The Discovery Channel will tell our children, ‘Isn’t it amazing that this thumb-using, web-weaving, flying frog evolved!’

All connection to reality has been replaced with buzzwords and hand-waving. It’s been said so many times that it sounds real. It’s not credible that any new evidence could shatter such faith.

Nevertheless, their genealogical arrangement remains strictly true, not only at the present time, but at each successive period of descent. All the modified descendants from A will have inherited something in common from their common parent, as will all the descendants from I; so will it be with each subordinate branch of descendants at each successive stage.

i.e. there is a true pattern of descent(with nested ‘subordinate’ branches). But if some descendends are radically changed it’s difficult for us to place them in that true pattern even though “their genealogical arrangement remains strictly true”

As for the second one, here’s what follows:

We shall see this by turning to the diagram [A tree!]: the letters, A to L, may represent eleven Silurian genera, some of which have produced large groups of modified descendants, with every link in each branch and sub-branch still alive; and the links not greater than those between existing varieties. In this case it would be quite impossible to give definitions by which the several members of the several groups could be distinguished from their more immediate parents and descendants. Yet the arrangement in the diagram [a tree remember] would still hold good and would be natural; for, on the principle of inheritance, all the forms descended, for instance from A, would have something in common. In a tree we can distinguish this or that branch, though at the actual fork the two unite and blend together

Since joining the blogosphere in 2004, I have consistently said that if Darwin has entitled his book, Origin of Adaptations I wouldn’t have any problems with it.

Or, as a contemporary critic of Darwin said: “As to what is old in the theory, the theory is correct; as to what is new in the theory, it is wrong.” Any half-witted soul can figure out that biological forms are plastic; that’s what breeders do.

1- You wouldn’t know it’s genealogical arrangement. It is possible to have grandchildren without any of your DNA. Also nesting is not subordinate. Nesting is groups within groups- that is what a nested hierarchy is -> groups WITHIN groups.

That said a family “tree” doesn’t even form a tree and that is decent with modification at the lowest level (sexually reproducing organisms)- no nested hierarchy in a family tree.

2- If they blend together at the fork there isn’t anything that keeps them blended all the way through.

Math in biology is only relevant upon a presumption that biological change happened and happens on happanchance.
Otherwise math folks got nothing to say about evolution if they put their mind to math stuff.
I was banned on Jason Rosenhouse blog etc for no good reason except difference of opinion and found him unreasonable generally.
Anyways biology don’t need help from geology or math to makes its cases.
Math simply helps creationism(s) because of the great odds evolutions demands as a constant operation.